1. Field of the Invention:
The present invention relates to a method for producing an ozone gas that is available for pasteurization, sterilization, bleaching or the other general oxidation, and an apparatus for producing the same, that is, an ozonizer.
More particularly, the invention relates to a method and an apparatus for producing an ozone gas, in which air or oxygen is fed into a silent discharge generating region or a corona discharge generating region of an electric field device having a layer formed of dielectric such as glass, alumina ceramic or the like disposed between a pair of electrodes and thereby they are ozonized.
2. Description of the Prior Art:
Heretofore, in the above-described type of method and apparatus, a high voltage power supply is connected between a linear electrode and a two-dimensional electrode forming the above-mentioned pair of electrodes or between one two-dimensional electrode and another two-dimensional electrode forming the pair of electrodes to generate a silent discharge or a corona discharge in the space zone between these electrodes, and consequently, an ionic current flows through the discharge generating region in this space zone and thus ozonizes the gas to be ozonized, that is, the oxygen gas present in this region. However, due to heat generating phenomena during that process, the gas to be ozonized is expanded, hence the density of the gas becomes lower than that in the standard state before the above-described ionic current begins to flow through the region, and consequently, an ozone generating efficiency is lowered.
In order to prevent this, heretofore, cooling was effected so as to bring the temperature at the silent discharge or corona discharge generating region of the above-described electric field device back to the proximity of the temperature of the atmospheric air before heat is generated in that region, that is, the temperature of the atmospheric air under the standard state, through forcible cooling by water-cooling the electric field device or by forming cooling fins or the like on the outside of the electric field device.
However, since heat is continuously generated during discharge in the silent discharge or corona discharge generating region, it was as a practical matter difficult to lower the temperature in this region to the temperature of air in the standard state before commencement of the discharge, that is, before commencement of the operation of the apparatus, and so it was compelled to operate the apparatus at about 60.degree. C.
Therefore, the ozone generating efficiency was about 5%, and it was considered impossible to raise the efficiency up to a higher value.